JPH04309802A - Two dimensional size measuring device for thin plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

[Object of the invention]

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin plate two-dimensional dimension measuring device for measuring dimensions related to the two-dimensional shape of a thin plate such as a cut steel plate used in a magnetic core of a power transformer.

0003

2. Description of the Related Art For example, as shown in FIG. 11, a three-legged core for a power transformer magnetic core is made by laminating thin steel plates whose ends are cut at a right angle or at an angle of 45 degrees, and into which windings are inserted. It consists of three core legs A1, A2, A3 and four yokes B1, B2, B3, B4 that form a closed magnetic path between these three core legs A1, A2, A3.
In order to match the shape of the winding and increase the effective cross-sectional area, each core leg is laminated so that the cross-section has a substantially circular shape as shown in FIG. 12. In addition, at the joint between the core leg A1 and the yokes B1 and B3, as shown in FIG.
, B3 are stacked up and down by an eccentric amount e from the center, so that the thin plates forming the core leg A1 and the yokes B1 and B3 overlap each other, thereby achieving good magnetic and mechanical coupling. I have to. Here, as shown in FIG. 14, the cutting inclination angles θ1 and θ
2. If a core is formed using a thin plate with variations in the cutting length L at the center of the thin plate, the joints between the core legs and the yoke as shown in Figure 1.
Gaps G1 and G2 as shown in FIG. 5 are generated, causing core loss and an increase in excitation current, which adversely affects the performance of the transformer. Therefore, it is necessary to precisely measure the dimensions of the large number of thin plates that make up the transformer magnetic core after cutting them, and to assemble the core using thin plates with uniform cut dimensions.

By the way, since the thin plates used in such power transformer magnetic cores are generally several thousand millimeters long, their dimensions are measured using a dedicated measuring device. That is, as shown in FIG. 16, in the conventional measuring device, a movable stage 23 moves along linear motion rails 25a and 25b mounted parallel to each other on a fixed table 24.
The magnifying projector 26 moves in the Y direction along the linear motion rail 27 mounted on the moving stage 23 at right angles to the linear motion rails 25a and 25b. It is configured to move on a thin plate 28 placed above, and the amount of movement of the enlarged projector 26 in the X direction is detected by a linear scale 29 and a linear scale head 30, and the coordinates in the X direction are displayed numerically on a display 31. The amount of movement of the enlarged projector 26 in the Y direction is detected by the linear scale 32 and the linear scale head 33, and the coordinates in the Y direction are displayed numerically on the display 34. And thin plate 28
Press the lower side of the thin plate against the reference guide 35 installed parallel to the linear motion rails 25a and 25b so that the longitudinal direction of the thin plate is Y.
Place it on the fixed table 24 so that it matches the direction. Then, the worker holds the handles 36 and 37 and moves the magnifying projector 26 while looking at the screen 38 on which the thin plate 28 is enlarged and projected, and the enlarged projection is projected to a position where the center intersection 39 of the screen 38 coincides with the dimension measurement point of the thin plate 28. The coordinates of the dimension measurement points of the thin plate 28 are displayed on the displays 31 and 34 by moving the device 26. In this way, by measuring the coordinates of several dimension measurement points and calculating the coordinates of each measurement point, the cutting length L and the cutting inclination angles θ1 and θ2 at the center of the thin plate are determined.

[0005]

[Problems to be Solved by the Invention] However, in the above-mentioned measuring device, it is necessary to precisely align the center intersection 39 of the screen 38 with the dimension measurement point, and for this purpose, the operator has to delicately move the magnifying projector 26. This required a lot of time and resulted in poor measurement efficiency. In addition, measurement accuracy depends on the skill of the worker, and measurements vary depending on the worker, resulting in low measurement reliability and the possibility of adversely affecting the performance of the transformer.

The present invention has been made in view of the above circumstances, and its purpose is to accurately and quickly measure dimensions related to the two-dimensional shape of thin plates such as cut steel plates used in magnetic cores of power transformers. An object of the present invention is to provide a two-dimensional dimension measuring device for thin plates. [Structure of the invention]

[0007]

[Means for Solving the Problems] In order to achieve the above object, the thin plate two-dimensional dimension measuring device of the present invention includes an imaging device that images a thin plate, and an imaging section of the imaging device that is connected to a thin plate dimension measurement point. An imaging section moving means for moving to a position where an image can be taken; an imaging section coordinate detection means for detecting the position of the imaging section moved by the imaging section moving means in two-dimensional coordinates; The image position detection means detects the position of the dimension measurement point, and the dimension calculation means calculates the dimensions related to the two-dimensional shape of the thin plate from the position of the imaging unit and the position of the dimension measurement point of the thin plate in the image. It is characterized by

[0008]

[Operation] Since the thin plate two-dimensional dimension measuring device of the present invention is constructed as described above, the imaging unit is moved to a position where the dimension measurement point of the thin plate can be imaged by the imaging unit moving means, and the image is captured by the imaging device. The position of the dimension measurement point of the thin plate in the image is determined by the image position detection means, and the position of the entire captured image, that is, the position to which the imaging unit was moving at the time when the imaging device imaged the thin plate, is determined by the image position detection means. The two-dimensional coordinates are determined by the partial coordinate detection means. The dimension calculation means calculates the two-dimensional coordinates of the dimension measurement point of the thin plate from the position in the image of the dimension measurement point of the thin plate and the two-dimensional coordinates of the moved imaging unit, and further calculates the two-dimensional coordinates of the dimension measurement point of each dimension measurement point. Since the dimensions related to the two-dimensional shape of the thin plate are calculated by calculating the coordinates, the dimensions of the thin plate of the cut steel plate can be measured accurately and quickly.

[0009]

[Embodiment] An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of an embodiment of the present invention. In the figure, an ITV (industrial television) camera 1 takes an image of a thin plate 2, which is placed on a fixed table 4 with its lower side pressed against a reference guide 3. The moving stage 5 moves in the X direction along linear motion rails 6a, 6b mounted parallel to the reference guide 3, and the ITV camera 1 moves along linear motion rails 6a, 6b mounted at right angles to the linear motion rails 6a, 6b. 7 in the Y direction. That is, the ITV camera 1 is designed such that an operator can take an image of any position on the thin plate 2 by holding the handle 8 and moving the thin plate 2 in the X direction or the Y direction. The amount of movement of the ITV camera 1 in the X direction is detected by a linear scale 9 attached to the fixed table 4 and a linear scale head 10 that moves together with the moving stage 5, and is counted as a coordinate in the X direction by a counter circuit 11. It is sent to the arithmetic unit 12. Also, ITV camera 1
The amount of movement in the Y direction is detected by the linear scale 13 attached to the moving stage 5 and the linear scale head 14 that moves together with the ITV camera 1.
After being counted as a coordinate in the Y direction, it is sent to the data calculator 12.

On the other hand, an image signal of the thin plate 2 taken by the ITV camera 1 is sent to a monitor television 16 and displayed on a screen, and is also converted into a digital signal by an A/D converter 17 and sent to an image memory 18. Then, the image processing circuit 19 reads the image data from the image memory 18 and determines the position of the dimension measurement point of the thin plate 2 in the image.
The information is sent to the data calculator 12.

The data calculator 12 also calculates the position of the thin plate 2 from the two-dimensional coordinates of the position of the ITV camera 1 sent from the counter circuits 11 and 15 and the position in the image of the dimension measurement point of the thin plate 2 sent from the image processing circuit 19. The two-dimensional coordinates of the positions of the dimension measurement points are calculated, and the dimensions of the thin plate 2 are calculated from the thus determined two-dimensional coordinates of the positions of each dimension measurement point of the thin plate 2 and sent to the dimension display 20. The control circuit 21 controls the entire measuring device, especially the start button 22.
It has a function of controlling the flow of calculating the two-dimensional coordinates of the position of the dimension measurement point of the thin plate 2 at that time in response to being pushed.

Next, the operation of the measuring device of this embodiment constructed as described above will be explained with reference to the case where the cutting length at the center of a thin plate is measured.

First, as shown in FIG. 2, move the ITV camera 1 to the lower side of the thin plate 2, and press the start button 2 while the lower end of the thin plate 2 is displayed on the screen of the monitor television 16.
When 2 is pressed, the amount of movement of the ITV camera 1 in the Y direction at that time is determined by the linear scale 13 and the linear scale head 14.
is detected by the counter circuit 15, counted as Y-direction coordinate Y11, and sent to the data calculator 12.
The image signal of the V camera 1 is sent to an A/D converter 17, converted into a digital signal, and stored in an image memory 18 as image data. FIG. 3 is a schematic diagram of the image data at this time. FIG. 4 shows the gray level g1 in an arbitrary vertical line L1 that coincides with the Y direction in this image.
, g2 and g3 are shown. This density level g1
, g2, and g3 are the shading levels of the thin plate 2, reference guide 3, and fixed table 4, respectively, and the coordinate y1 is the ITV
This is the position of the lower end of the thin plate 2 in the Y direction in the image captured by the camera 1. The image processing circuit 19 scans the image data of the line L1 and searches for a position where the gray level changes rapidly, thereby determining the coordinate y1 and sending it to the data calculator 12. Furthermore, the data calculator 13 further calculates the Y-direction coordinate Y of the ITV camera 1.
11 and the Y-direction coordinate y1 of the lower end of the thin plate 2 in the image captured by the ITV camera 1 to obtain the Y-direction coordinate Y1 of the lower end of the thin plate 2.

Next, as shown in FIG. 5, move the ITV camera 1 to the upper side of the thin plate 2, and press the start button 2 while the upper end of the thin plate 2 is displayed on the screen of the monitor television 16.
When 2 is pressed, the Y-direction coordinate Y2 of the upper end of the thin plate 2 is obtained in the same way as when the Y-direction coordinate Y1 of the lower end of the thin plate 2 was obtained above. Further, the data calculator 12 calculates a coordinate Y3 intermediate between the coordinates Y1 and Y2. This coordinate Y3 is the coordinate of the center line of the thin plate 2 in the Y direction.

Furthermore, as shown in FIG.
When the start button 22 is pressed while the left edge of the thin plate 2 is moved to the left almost on the center line of the thin plate 2 and the left end of the thin plate 2 is reflected on the image on the monitor television 16, the amount of movement of the ITV camera 1 in the X direction and The amount of movement in the Y direction is detected by the linear scale 9 and the linear scale head 10, and the linear scale 13 and the linear scale head 14, respectively, and the counter circuit 11 and the counter circuit 15 detect the coordinate X3 in the X direction.
1 and the coordinate Y31 in the Y direction, and sent to the data calculator 12, respectively. At the same time, ITV camera 1
The image signal is sent to the A/D converter 17, converted into a digital signal, and stored in the image memory 18 as image data. A schematic diagram of this image data is shown in FIG. In FIG. 7, the data calculator 13 subtracts the Y-direction coordinate Y31 of the ITV camera 1 from the already calculated Y-direction coordinate Y3 of the center line of the thin board 2. The coordinate y3 is obtained as the position of the center line in the Y direction. Figure 8 shows the coordinate y3 from the image data.
The gray level g4 in one horizontal line L3 of
, g5. This density level g4, g5
are the shading levels of the thin plate 2 and fixed table 4, respectively. The coordinate x3 is the position of the left end of the center of the thin plate 2 in the X direction in the image captured by the ITV camera 1. The image processing circuit 19 scans the image data of the line L3 and searches for a position where the gray level changes rapidly, thereby determining the coordinate x.
3 and sends it to the data calculator 12. Furthermore, the data calculator 12 calculates the X-direction coordinate X31 of the ITV camera 1,
The X-direction coordinate x3 of the center left end of the thin plate 2 in the image captured by the ITV camera 1 is added to obtain the X-direction coordinate X3 of the center left end of the thin plate 2.

Next, as shown in FIG. 9, the ITV camera 1 is moved to the right almost on the center line of the thin plate 2, and the start button 22 is pressed while the right end of the thin plate 2 is displayed on the screen of the monitor television 16. Then, the X-direction coordinate X4 of the center right end of the thin plate 2 is obtained in the same manner as when the X-direction coordinate X3 of the center left end of the thin plate 2 was obtained above. Then, the data calculator 12 calculates the cutting length L at the center of the thin plate 2 by subtracting the coordinate X3 from the coordinate X4, and displays the length L on the dimension display 20.

As mentioned above, in this embodiment, each of the four measurement points (lower end, upper end, center left end, center right end) necessary for determining the cutting length L at the center of the thin sheet 2 is By moving the ITV camera 1 to a position within the range of the image captured by the camera 1, the accurate position of each measurement point is detected and the cutting length L at the center of the thin plate 2 is calculated, so each worker can measure the It is possible to perform measurements with high accuracy and no variation. Moreover, since the measurement work is very simple, the cut length of the thin plate can be measured quickly.

It should be noted that the present invention is not limited to the above embodiments, and may be modified without departing from the spirit thereof. For example, in the above embodiment, a case was described in which the cutting length at the center of a thin plate was measured.
As shown in Figure 0, the coordinates (X5, Y5) and (X6, Y6) of the measurement point P1 and the measurement point P2 of the thin plate, respectively, are
) can be used to measure the cutting angle θ, and various other dimensions related to the two-dimensional shape of the thin plate can also be measured. In addition, in the above embodiment, the measured dimensions are displayed on the dimension display, but the present invention is not limited to this. It is also possible to determine whether the measured dimensions are within the allowable dimensions, and to store the measured dimensions in the storage device. It may be configured so that it can be stored and referred to later as needed. Further, in the above embodiment, the ITV camera was moved manually by a worker, but mechanical power such as a motor may also be used. Furthermore, I.T.
The amount of movement of the V camera was detected using a linear scale, but
The amount of linear movement of the ITV camera may be converted into the amount of rotation, and the amount of movement may be detected using a pulse encoder or the like.

[0019]

[Effects of the Invention] As explained above, two of the thin plates of the present invention
According to the dimensional measurement device, it is possible to accurately and quickly measure the dimensions of a thin plate such as a cut steel plate used in a power transformer magnetic core.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention.

FIG. 2 is a diagram for explaining image data displayed on a monitor television screen by moving an ITV camera below a thin plate.

FIG. 3 is a schematic diagram of the image data in FIG. 2.

FIG. 4 is a diagram showing the gray level of an arbitrary vertical line that coincides with the Y direction from the image data of FIG. 2;

FIG. 5 is a diagram for explaining image data displayed on the monitor television screen by moving the ITV camera above the thin plate.

FIG. 6 is a diagram for explaining image data displayed on a monitor television image when the ITV camera is moved to the left approximately on the center line of the thin plate.

FIG. 7 is a schematic diagram of the image data of FIG. 6.

8 is a diagram showing the gray level of an arbitrary vertical line that coincides with the Y direction from the image data of FIG. 6; FIG.

FIG. 9 is a diagram for explaining image data displayed on a monitor television screen when the ITV camera is moved to the right approximately on the center line of the thin plate.

FIG. 10 is a diagram for explaining a method of measuring the cutting angle of a thin plate.

FIG. 11 is a configuration diagram of a three-leg iron core used in a conventional power transformer.

FIG. 12 is a perspective view of the core leg of FIG. 11;

FIG. 13 is an enlarged view of the joint between the core leg and the yoke in FIG. 11;

FIG. 14 is a diagram for explaining a conventional method of cutting a thin steel plate.

FIG. 15 is an enlarged view of the joint between a core leg made of poorly cut thin steel plate and a yoke.

FIG. 16 is an overall configuration diagram of a conventional measuring device.

[Explanation of symbols]

1... ITV camera, 2... thin plate, 3... reference guide, 4... fixed table, 5... moving stage, 6a, 6b... linear motion rail, 7... linear motion rail, 8... handle, 9, 13... linear scale, 10 , 14... linear scale head, 11,
15... Counter circuit, 12... Data calculator, 16... Monitor television, 17... A/D converter, 18... Image memory, 19... Image processing circuit, 20... Dimension display, 21... Control device, 22... Start button.

Claims (1)

[Claims] 1. A thin plate two-dimensional dimension measuring device for measuring dimensions related to the two-dimensional shape of a thin plate such as a magnetic core of a power transformer, comprising: an imaging device for imaging the thin plate; and an imaging unit of the imaging device. an imaging unit moving means for moving to a position where a dimension measurement point of the thin plate can be imaged; an imaging unit coordinate detection means for detecting the position of the imaging unit moved by the imaging unit moving means using two-dimensional coordinates; image position detection means for detecting the position of the dimension measurement point of the thin plate in the image; and calculating dimensions related to the two-dimensional shape of the thin plate from the position of the imaging unit and the position of the dimension measurement point of the thin plate in the image. 1. A two-dimensional dimension measuring device for a thin plate, comprising: a dimension calculation means.